Uveitis is inflammation of the uveal tract (see figure Cross-section of the eye Cross-section of the eye Uveitis is defined as inflammation of the uveal tract—the iris, ciliary body, and choroid. However, the retina and fluid within the anterior chamber and vitreous are often involved as well.... read more ). Uveitis is classified anatomically as
Anterior uveitis: Localized primarily to the anterior segment of the eye, includes iritis (inflammation in the anterior chamber alone) and iridocyclitis (inflammation in the anterior chamber and anterior vitreous)
Intermediate uveitis: Localized to the vitreous cavity and/or pars plana (part of the ciliary body that extends posteriorly beyond the junction of the iris and sclera)
Posterior uveitis: Any form of retinitis, choroiditis, or inflammation of the optic disk
Panuveitis: Inflammation involving anterior, intermediate, and posterior structures
Uveitis is also classified by onset (sudden or insidious), duration (limited or persistent), and course (acute, recurrent, or chronic).
Cross-section of the eye
The zonules of Zinn keep the lens suspended, and the muscles of the ciliary body focus the lens. The ciliary body also secretes aqueous humor, which fills the anterior and posterior chambers, passes through the pupil into the anterior chamber, and drains primarily via the Schlemm canal. The iris regulates the amount of light entering the eye by adjusting the size of its central opening, the pupil. Visual images are focused on the retina. The conjunctiva covers the eyeball and lines the upper and lower eyelids; it ends at the limbus. The cornea is covered with epithelium that is more sensitive than and differs from the conjunctival epithelium.
Etiology of Uveitis
Causes of anterior uveitis include
Idiopathic or postsurgical (most common cause)
Herpesvirus infection (herpes simplex virus Herpes Simplex Virus (HSV) Infections Herpes simplex viruses (human herpesviruses types 1 and 2) commonly cause recurrent infection affecting the skin, mouth, lips, eyes, and genitals. Common severe infections include encephalitis... read more [HSV], varicella-zoster virus Chickenpox Chickenpox is an acute, systemic, usually childhood infection caused by the varicella-zoster virus (human herpesvirus type 3). It usually begins with mild constitutional symptoms that are followed... read more [VZV], and cytomegalovirus Cytomegalovirus (CMV) Infection Cytomegalovirus (CMV, human herpesvirus type 5) can cause infections that have a wide range of severity. A syndrome of infectious mononucleosis that lacks severe pharyngitis is common. Severe... read more [CMV])
Causes of intermediate uveitis include
Idiopathic (most common)
Causes of posterior uveitis (retinitis) include
Idiopathic (most common)
HSV Herpes Simplex Virus (HSV) Infections Herpes simplex viruses (human herpesviruses types 1 and 2) commonly cause recurrent infection affecting the skin, mouth, lips, eyes, and genitals. Common severe infections include encephalitis... read more /VZV Chickenpox Chickenpox is an acute, systemic, usually childhood infection caused by the varicella-zoster virus (human herpesvirus type 3). It usually begins with mild constitutional symptoms that are followed... read more
Causes of panuveitis include
Idiopathic (most common)
Infrequently, systemic drugs cause uveitis (usually anterior). Examples are sulfonamides, bisphosphonates (inhibitors of bone resorption), rifabutin, cidofovir, and checkpoint inhibitors such as nivolumab and ipilimumab.
Symptoms and Signs of Uveitis
Symptoms and signs may be subtle and vary depending on the site and severity of inflammation.
Anterior uveitis tends to be the most symptomatic (especially when acute), usually manifesting with
Pain (ocular ache)
Decreased vision (to a variable degree)
Chronic anterior uveitis may have less dramatic symptoms and present with irritation or decreased vision.
Signs include hyperemia of the conjunctiva adjacent to the cornea (ciliary flush or limbal injection). Slit-lamp findings include keratic precipitates (white blood cell clumps on the inner corneal surface), cells and flare (a haze) in the anterior chamber (aqueous humor), and posterior synechiae. With severe anterior uveitis, white blood cells may layer in the anterior chamber (hypopyon).
Intermediate uveitis is typically painless and manifests with
The primary sign is cells in the vitreous humor. Aggregates and condensations of inflammatory cells often occur, appearing as "snowballs." Vision may be decreased because of floaters or cystoid macular edema, which results from fluid leakage from blood vessels in the macula. Confluent and condensed vitreous cells and snowballs over the pars plana (part of the ciliary body that extends posteriorly beyond the junction of the iris and sclera) may cause a classic "snowbank" appearance, which can be associated with neovascularization of the retinal periphery.
Posterior uveitis may give rise to diverse symptoms but most commonly causes floaters and decreased vision as occurs in intermediate uveitis. Signs include
Cells in the vitreous humor
White or yellow-white lesions in the retina (retinitis), underlying choroid (choroiditis), or both
Optic disk edema
Panuveitis may cause any combination of the previously mentioned symptoms and signs.
Serious complications of uveitis include profound and irreversible vision loss, especially when uveitis is unrecognized, inadequately treated, or both.
The most frequent complications include
Cataract Cataract A cataract is a congenital or degenerative opacity of the lens. The main symptom is gradual, painless vision blurring. Diagnosis is by ophthalmoscopy and slit-lamp examination. Treatment is... read more (secondary to the disease process and/or to corticosteroid treatment)
Glaucoma Overview of Glaucoma Glaucomas are a group of eye disorders characterized by progressive optic nerve damage in which an important part is a relative increase in intraocular pressure (IOP) that can lead to irreversible... read more (secondary to the disease process and/or to corticosteroid treatment)
Neovascularization of the retina, optic nerve, or iris
Cystoid macular edema (the most common cause of decreased vision in patients with uveitis)
Hypotony (an intraocular pressure that is too low to support the health of the eye)
Diagnosis of Uveitis
Ophthalmoscopy after pupil dilation
Uveitis should be suspected in any patient who has ocular ache Eye Pain Eye pain may be described as sharp, aching, or throbbing and should be distinguished from superficial irritation or a foreign body sensation. In some disorders, pain is worsened by bright light... read more , redness Red Eye Red eye refers to a red appearance of the opened eye, reflecting dilation of the superficial ocular vessels. Dilation of superficial ocular vessels can result from Infection Allergy Inflammation... read more , photophobia, floaters Floaters Floaters are opacities that move across the visual field and do not correspond to external visual objects. With aging, the vitreous humor can contract and separate from the retina. The age at... read more , or decreased vision. Patients with unilateral anterior uveitis have ocular ache in the affected eye if light is shined in the unaffected eye (true photophobia), which is uncommon in conjunctivitis.
Diagnosis of anterior uveitis is by recognizing cells and flare in the anterior chamber. Cells and flare are seen with a slit lamp and are most evident when using a narrow, intensely bright light focused on the anterior chamber in a dark room. Findings of intermediate and posterior uveitis are most easily seen after dilating the pupil. Indirect ophthalmoscopy Ophthalmoscopy The eye can be examined with routine equipment, including a standard ophthalmoscope; thorough examination requires special equipment and evaluation by an ophthalmologist. History includes location... read more (usually done by an ophthalmologist) is more sensitive than direct ophthalmoscopy. (NOTE: If uveitis is suspected, patients should be referred immediately for complete ophthalmologic evaluation.)
Many conditions that cause intraocular inflammation can mimic uveitis and should be considered in the appropriate clinical settings. Such conditions include severe conjunctivitis Overview of Conjunctivitis Conjunctival inflammation typically results from infection, allergy, or irritation. Symptoms are conjunctival hyperemia and ocular discharge and, depending on the etiology, discomfort and itching... read more (eg, epidemic keratoconjunctivitis), severe keratitis (eg, herpetic keratoconjunctivitis, peripheral ulcerative keratitis Peripheral Ulcerative Keratitis Peripheral ulcerative keratitis is inflammation and ulceration of the cornea that often occurs with chronic connective tissue diseases. Irritation and decreased vision result. (See also Introduction... read more ), and severe scleritis Scleritis Scleritis is a severe, destructive, vision-threatening inflammation involving the deep episclera and sclera. Symptoms are moderate to marked pain, hyperemia of the globe, lacrimation, and photophobia... read more .
Acute angle-closure glaucoma Angle-Closure Glaucoma Angle-closure glaucoma is glaucoma associated with a physically obstructed anterior chamber angle, which may be chronic or, rarely, acute. Symptoms of acute angle closure are severe ocular pain... read more can cause redness and severe pain similar to that of uveitis, which is why it is important to check intraocular pressure at every visit. Uveitis is often (but not always) associated with a low intraocular pressure, whereas pressure is typically high in acute angle-closure glaucoma. Uveitis also can be distinguished from angle-closure glaucoma by the absence of corneal haze and the presence of a deeper anterior chamber.
Other masqueraders include intraocular cancers Tumors of the Orbit Orbital tumors can be benign or malignant and arise primarily within the orbit or secondarily from an adjacent source, such as the eyelid, paranasal sinus, or intracranial compartment. Orbital... read more in the very young (typically retinoblastoma and leukemia) and in older people (intraocular lymphoma). Much less commonly, retinitis pigmentosa Retinitis Pigmentosa Retinitis pigmentosa is a slowly progressive, bilateral degeneration of the retina and retinal pigment epithelium caused by various genetic mutations. Symptoms include night blindness and loss... read more can manifest with mild inflammation, which may be confused with uveitis.
Treatment of Uveitis
Corticosteroids (usually topical) and sometimes other immunosuppressive drugs
Sometimes antimicrobial drugs
Sometimes surgical therapy
Treatment of active inflammation usually involves corticosteroids given topically (eg, prednisolone acetate 1% one drop every hour while awake) or by periocular or intraocular injection along with a cycloplegic-mydriatic drug (eg, homatropine 2% or 5% drops [if available] or cyclopentolate 0.5% or 1.0% drops, either drug given 2 to 4 times/day depending on severity). Antimicrobial drugs are used to treat infectious uveitis. Particularly severe or chronic cases may require systemic corticosteroids (eg, prednisone 1 mg/kg orally once/day), systemic noncorticosteroid immunosuppressive drugs (eg, methotrexate 15 to 25 mg orally once/week, adalimumab 40 mg subcutaneously every 1 to 2 weeks, or infliximab 4 to 10 mg/kg IV every 4 weeks), laser phototherapy, cryotherapy applied transsclerally to the retinal periphery, or surgical removal of the vitreous (vitrectomy) (1–3 Treatment references Uveitis is defined as inflammation of the uveal tract—the iris, ciliary body, and choroid. However, the retina and fluid within the anterior chamber and vitreous are often involved as well.... read more ).
1. Jaffe GJ, Dick AD, Brézin AP, et al: Adalimumab in patients with active noninfectious uveitis. N Engl J Med 8;375(10):932-43, 2016. doi: 10.1056/NEJMoa1509852
2. Lee J, Koreishi AF, Zumpf KB, et al: Success of weekly adalimumab in refractory ocular inflammatory disease. Ophthalmology S0161-6420(20)30333-X, 2020. doi: 10.1016/j.ophtha.2020.04.009
3. Kruh JN, Yang P, Suelves AM, et al: Infliximab for the treatment of refractory noninfectious uveitis: A study of 88 patients with long-term follow-up. Ophthalmology 121(1):358-364, 2014. doi: 10.1016/j.ophtha.2013.07.019
Inflammation of the uveal tract (uveitis) can affect the anterior segment (including the iris), intermediate uveal tract (including the vitreous), or posterior uvea (including the choroid, retina, and optic nerve).
Most cases are idiopathic, but known causes include infections, trauma, and autoimmune disorders.
Findings in acute anterior uveitis include aching eye pain, photophobia, redness closely surrounding the cornea (ciliary flush), and, on slit-lamp examination, cells and flare.
Chronic anterior uveitis may have less dramatic symptoms and present with eye irritation or decreased vision.
Intermediate and posterior uveitis tend to cause less pain and eye redness but more floaters and decreased vision.
Diagnosis is confirmed by slit-lamp examination and ophthalmoscopic examination (often indirect) after pupillary dilation.
Treatment should be managed by an ophthalmologist and often includes corticosteroids and a cycloplegic-mydriatic drug along with treatment of any specific cause.